Involvement of tyrosine kinase in capacitative Ca2+ entry pathway in rat glioma C6 cells.
Capacitative Ca2+ entry, a main pathway of Ca2+ entry evoked by receptor activation, is widely confirmed in various types of cells. However, the mechanism of the activation of capacitative Ca2+ entry is unknown. We checked the several candidates for the mechanism of capacitative Ca2+ entry pathway in rat glioma C6 cells using thapsigargin (TG), a microsomal Ca(2+)-ATPase inhibitor. Pretreatment with pertussis toxin did not affect the peak and sustained elevation of [Ca2+]i evoked by TG. Sodium nitroprusside and 8-bromo cyclic GMP did not affect an elevation of [Ca2+]i induced by TG. Phorbol 12-myristate 13-acetate, an activator of protein kinase C (PKC), and staurosporine, an inhibitor of PKC, did not modify an increase in [Ca2+]i induced by TG. Okadaic acid, an inhibitor of phosphatase, did not affect an increase in [Ca2+]i evoked by TG. Pretreatment with colchicine and cytochalasin D, drugs disrupting cytoskeleton, had no effect on a rise of [Ca2+]i induced by TG. Genistein and erbastatin analog, inhibitors of tyrosine kinase, inhibited an elevation of [Ca2+]i evoked by TG in a dose-dependent manner. The present results suggest that tyrosine kinase regulates capacitative Ca2+ entry into rat glioma C6 cells.
Takemura
H
H
Department of Pharmacology, School of Medicine, Sapporo Medical University, Japan.
Imoto
K
K
Sakano
S
S
Kaneko
M
M
Ohshika
H
H
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002460:Cell Line; D006152:Cyclic GMP / Q000378:metabolism; D003599:Cytoskeleton / Q000187:drug effects / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D019204:GTP-Binding Proteins / Q000378:metabolism; D005910:Glioma / Q000201:enzymology / Q000378:metabolism*; D009569:Nitric Oxide / Q000502:physiology; D037342:Pertussis Toxin; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors / Q000378:metabolism; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D051381:Rats; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D004791:Enzyme Inhibitors; D010566:Virulence Factors, Bordetella; D009569:Nitric Oxide; D037342:Pertussis Toxin; D011505:Protein-Tyrosine Kinases; D011493:Protein Kinase C; D010749:Phosphoprotein Phosphatases; D019204:GTP-Binding Proteins; D006152:Cyclic GMP; D002118:Calcium